1. Field of the Invention
The present invention relates to a system and method for detecting a surrounding environment, and more particularly, to a system and method being applied to a vehicle and using a primary display unit, a plurality of secondary display units and different types of detectors for detecting a surrounding environment.
2. Description of Related Art
There are many types of detectors that can be used on vehicles to detect a surrounding environment, such as image detectors, supersonic radars, optical laser radars, millimeter wave/microwave radars and infrared radars. The most commonly used among them are supersonic radars for preventing a vehicle from bumping by short distance detection at parking. Besides, image detectors are becoming more popular, as they can accurately display the types and positions of nearby objects in the surroundings. Optical laser radars have the longest detection distance and thereby provide positional measurement that is yet the most accurate. The application of millimeter wave/microwave radars has been the widest so far. Their detection ranges can be adjusted accordingly and be working at either low or high speed of movement. Among all, infrared radars provide the most precise angular measurement.
However, the conventional detectors have their drawbacks. For instance, supersonic radars can only be used at slow speed, like parking a vehicle, because the sound velocity is low and susceptible to Doppler effects. Optical laser radars tend to be affected by unfavorable weather conditions such as rains or fogs. Image detectors, on the other hand, require a complicated calculation to obtain the information, and still have room for improvement in errors. Therefore, in practice, each type of the detectors has its own limits.
In addition, the detected data depend on the position of the detector in a vehicle. For example, detectors installed in the front of the vehicle may acquire different measurements as detecting the same object before the vehicle depends on whether the detectors are mounted on the central axis of the vehicle or near the headlights, even though the detectors are of the same properties and adopt the same media for detection. It is because the detector installation positions relative to the object position are different. Furthermore, different types of detectors by using various detection media and applying principles will result in different forms of data. For instance, the obstacle data collected by infrared radars only provide two-dimensional information while those collected by millimeter wave/microwave radars provide three-dimensional information.
It is difficult to combine different types of detectors because each has its specific application conditions. In prior arts, a certain type of detectors is usually only responsible for a certain application. Referring to FIG. 1, a conventional vehicle takes advantage of supersonic radars to extend the detectable range of wing mirrors 10 with the radar coverage 12. However, owing to the drawbacks described above, any single type of detectors can neither provide accurate measurements nor meet the various requirements of driving conditions.
As a result, it is desirable to design a system for detecting a surrounding environment, which is achieved by the combination of functions of different types of detectors complementary to one another. The system integrates the detected data of different types of detectors and obtains the accurate positions of target obstacles.